html,
body {
    height: 100%;
    margin: 0;
    font-size: 16pt;
}

#editor {
    display: flex;
    width: 100%;
    height: 100%;
}

#controls {
    background: #AAA;
    padding: 5px;
}

#c {
    width: 100%;
    height: 100%;
    display: block;
}

.gutter {
    background-color: #eee;
    background-repeat: no-repeat;
    background-position: 50%;
}

.gutter.gutter-horizontal {
    cursor: ew-resize;
    background-image: url(https://threejs.org/manual/examples/'')
}